I discovered this on my annual backpacking trip during a particularly cold winter. I sleep in a zero degree bag in a hammock, but my bag has most of the insulation on top so my back was freezing. Next year I brought a nice thick blanket to line the hammock and I’ve always been comfortable since.
Your weight compresses most of the insulation beneath you, and the hammock itself provides less than no insulation. If you aren't, you should put the blanket on the outside of the bottom of the hammock (suspended beneath it), so it has more volume and thus insulation.
Interesting, I wouldn't have thought of that. The blanket is pretty dense and relatively incompressible, but I'll have to try that and see if the difference is noticeable (if I can figure out how to attach it like that).
